Discover the Amazing Forest Researchers Found in Giant Sinkhole in China

A sinkhole is a section of land that has collapsed in on itself, sometimes for many feet. If the sinkhole is big enough, it can swallow an entire house. But in May 2022, scientists discovered a sinkhole in China that conceals an entire amazing forest inside of it. Not only that, this forest harbors species of animals that scientists have never seen before!

You’ll find this sinkhole in the Guangxi Zhuang Autonomous Region in China’s Leye County near a village called Ping’e. Huge sinkholes aren’t rare in this part of the country, and this latest sinkhole is the 30th one discovered. Indeed, UNESCO designated the region as a world heritage site, not just for the sinkholes but for its breathtaking rock formations as well.

The prevalence of sinkholes is due to Leye County’s karst landforms. Karst occurs when water slowly dissolves carbonate rocks like limestone. This creates caves, underground streams, and eventually, sinkholes when everything collapses in on itself. Sometimes, a number of sinkholes coalesce and create plojes, which are long fields with high walls and flat floors.

The Sinkhole Itself

The Eagle Sinkhole is an example of a tiankeng, Chinese for “heavenly pit.” It is 1,004 feet long, about 500 feet wide, 630 feet deep, and has a volume of 176 million cubic feet. This sinkhole not only harbors an amazing forest, but an underground lake with waters of a nearly fluorescent turquoise blue. They also found collapsed caves and signs of rivers that flowed eons ago. Scientists estimate that the sinkhole is about 100,000 years old.

What Lives in the Sinkhole

New Species of Eagle?

Researchers nicknamed the sinkhole The Eagle because they discovered it after noticing eagles flying above it. Interestingly, these eagles appear to be of an unknown species.

Thorny Bamboo with Square Stems

In addition to a family of unspecified eagles, scientists also discovered trees as tall as 130 feet and shrubbery at should height, including vines. Such an abundance of plant life is amazing since the sunlight that falls into a sinkhole is limited. Still, they have identified a species of thorny bamboo, Chimonobambusa quadrangularis, that botanists claim only grows well when conditions such as light, soil, and moisture are good.

This bamboo is unusual because it’s thorny and has square and hollow stems. Its thorns are found at the joints of the stems, or culms, and can be between 0.79 and 1.18 inches long. C. quadrangularis bamboo is native to China. It grows best in moist soil and dappled sun and shade, which The Eagle offers. This species of bamboo can grow as high as 9 feet and its culms are about 0.79 of an inch in diameter. The plant holds both male and female flowers and is wind pollinated. It’s called a running bamboo because it aggressively reproduces through underground rhizomes and can become invasive. People use the tender young shoots of C. quadrangularis as food.

Beautiful Heliconia Plants Also Grow in the Sinkhole

Photos of the sinkhole’s amazing forest show plants with long, wide leaves very much like those of the banana plant. These are actually leaves of its cousin, the wild plantain, or heliconia. These plants are herbaceous, which means their stems are green and pliant as opposed to rigid and woody. Because they are usually native to the tropical forests in South and Central America, finding them in a Chinese sinkhole is especially interesting.

Heliconia plants can grow as tall as 15 feet, and their leaves are simple and can also be very long. Some heliconia leaves can grow to 10 feet in length, and each leaf absorbs and uses sunlight depending on where it’s found on the plant. Heliconias produce flowers in panicles, and like dogwoods, the flowers are actually tiny and enveloped by colorful bracts that look like flowers. Many heliconias have evolved the shapes of their flowers to attract specific types of hummingbirds. Eventually, heliconias produce blackberry-colored fruit that is eaten by birds. The birds then disperse the seeds.

Though The Eagle is deep, it doesn’t compare to the largest sinkhole in the world, Xiaozhai Tiankeng. This massive sinkhole is 2,172 feet deep and found in Chongqing, China. It isn’t a recent discovery and has been known to the people in the area since antiquity. Because of this, its flora and fauna have been widely studied. Xiaozhai Tiankeng is home to animals such as the critically endangered Chinese giant salamander and the clouded leopard.